It's Qt UI so you have to get the container hWnd and use that:
QtWidgets = python.import "PySide2.QtWidgets"
setCommandPanelTaskMode #motion
cpHWnd = ((dotNetClass "Autodesk.Max.GlobalInterface").Instance.UtilGetCoreInterface16()).CommandPanelRollup.Hwnd
cpRoot = (windows.getHWndData cpHWnd)[7]
motionHWnd = (windows.getChildrenHWnd cpRoot)[3][1]
motionWidget = QtWidgets.QWidget.find motionHWnd
for w in motionWidget.children() as array
where w.__class__ == QtWidgets.QPushButton and w.text() == "Parameters" do
w.click()
that's what i find.
but I'm using max 2019 version, there is a some issue when getting hwnd function ( return float value )
So I solved the problem by getting all the QT widgets and iterating them.
thank you!!!
Whatever works 🙂 In pre-2018.2 or so CommandPanelRollup.Hwnd was broken anyway (always returned zero) so you had to do a lot of gymnastics to get the right handle (different ways when it's undocked, if you get it by the string you have to cover localized versions etc).